I went over that wall exercises with Tom H. It is revelevant to start to feel the pressure with the joints and identify them. It helps most guys to start with the hands higher than the shoulders. Any lower and its easier to engage isolated muscles in the shoulders and triceps. Opening up takes a while and in my view one should never stop. We love the wall.
Once they can identify and open up, then start moving the body in say a hoola hoop fashion to identify that the hips and toros are free from any tension from the feet and hands. Typically even when trained men move they will put weight in their hands unequally and unknowingly. In the smallest sense not truly feeling or controlling what they are doing with their own hands. Remaining neutral with an "empty gi" feel while offering any manner or pressure with the hands becomes a training tool on a wall. Changing your feet, by cross stepping, with the hips and knees remaining open now helps identify the knee/elbow, sternum/hip hands/feet seqentially remaining open. Most guys you can get to sart to open up (after they start to let go of the shoulder) and feel the hand and feet while on one foot. Then get them relaxing and moving the whole body while on the one foot and just feeling hand and foot. Then as soon as they start to use the other foot and transfer weight they feel it instantly that the pressure is uneven in each hand.
There are numerous ways that this becomes useful in grappling and in control of their center. Not all of which are in the hands.

Ever notice that your fingers are now like drills when you contact people?
Good Post
Cheers
Dan